CN111809141B - Composite permeable layer and QPQ treatment process thereof - Google Patents
Composite permeable layer and QPQ treatment process thereof Download PDFInfo
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- CN111809141B CN111809141B CN202010699992.7A CN202010699992A CN111809141B CN 111809141 B CN111809141 B CN 111809141B CN 202010699992 A CN202010699992 A CN 202010699992A CN 111809141 B CN111809141 B CN 111809141B
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/40—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using liquids, e.g. salt baths, liquid suspensions
- C23C8/58—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using liquids, e.g. salt baths, liquid suspensions more than one element being applied in more than one step
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/80—After-treatment
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Abstract
The invention relates to a second generation QPQ treatment process of a hydraulic cylinder, which is positioned on the inner surface of the hydraulic cylinder and comprises a compound layer, an intermediate layer and a diffusion layer which are sequentially stacked from inside to outside; the compound layer is composed of surface Fe 3 O 4 Dense Fe 3 N、Fe 4 N is formed; the thickness of the compound layer is 20 to 100 mu m, and the hardness is HV 0.1 800 to 1100. The invention also provides a QPQ treatment process of the composite permeable layer, which is suitable for an outer cylinder, a middle cylinder, a plunger or a piston rod of a hydraulic support on a hydraulic cylinder.
Description
Technical Field
The invention relates to a second generation QPQ treatment process of a hydraulic cylinder, in particular to a composite permeable layer and a QPQ treatment process thereof.
Background
QPQ treatment, which is an abbreviated form of Quench-Polish-Quench. The method is characterized in that a ferrous metal part is put into two different penetrating agents with different properties, and a plurality of elements penetrate into the surface of the metal to form a composite penetrating layer, so that the purpose of modifying the surface of the part is achieved. It is not quenched, but achieves the effect of surface quenching, so it is called QPQ abroad. The technology is called as a nitrogen-oxygen composite treatment technology in China.
Although the QPQ treatment has been widely applied abroad, the QPQ treatment needs a complete set of special equipment, and the investment in the early stage is high, so most enterprises in China still use the hard chromium plating process due to cost consideration.
The hard chromium plating process can ensure that the surface of the part has higher wear resistance and corrosion resistance at the same time, so the hard chromium plating process has wide application in various mechanical parts, particularly in the field of hydraulic systems of coal mines, and can hardly replace the hard chromium plating process by other methods due to the cost and the like. However, hexavalent chromium ions are generated during the hard chromium plating process, and not only are the hexavalent chromium ions seriously polluting the environment, but also are difficult to eliminate than cyanide.
Therefore, it is imperative to replace the hard chrome plating process entirely. In consideration of the high investment cost of the existing QPQ treatment process, it is necessary to develop a QPQ treatment process with lower investment cost.
Disclosure of Invention
The invention provides a composite permeable layer formed by a second generation QPQ treatment process, which is used for solving the problem of higher input cost of the existing QPQ treatment.
The composite permeable layer comprises a compound layer, a middle layer and a diffusion layer which are sequentially stacked from inside to outside; the compound layer is composed of surface Fe 3 O 4 Dense Fe 3 N、Fe 4 N is formed; the compound layer has a thickness of 20 to 100 μm and a hardness of HV 0.1 800～1100。
The invention has the advantages that:
the input cost is few, and the composite bed that forms can satisfy the special demand of pneumatic cylinder internal surface, through the compound layer of inlayer, can make compound ooze the layer and become whole with pneumatic cylinder base member zonulae occludens, and the compound layer has the thickness and the hardness of broad range, can satisfy the pneumatic cylinder base member needs of multiple different grade type.
Further, the intermediate layer is a nitrogen-containing austenite layer, and the thickness of the intermediate layer is 10 to 80 μm.
The strength and the corrosion resistance of the composite seeping layer can be increased through the intermediate layer.
Further, the thickness of the diffusion layer is 150 to 700 μm.
The thickness of the outermost diffusion layer can increase the fatigue strength, the wear resistance and the corrosion resistance of the whole composite permeation layer.
Further, the compound layer is a composite wear-resistant anticorrosive layer, and the corrosion resistance of the diffusion layer in a salt spray test reaches 500-1200 hours.
By thus providing the diffusion layer, corrosion resistance and wear resistance are effectively increased.
The invention also provides a QPQ treatment process of the composite permeable layer, which comprises the following steps of:
cleaning a liquid pressure cylinder substrate;
secondly, the hydraulic cylinder is basically placed in a preheating furnace for preheating treatment, the preheating temperature is 320-480 ℃, and the time is 30-240 min;
thirdly, putting the preheated hydraulic cylinder matrix into a nitriding furnace for nitriding treatment; nitriding temperature is 380-650 deg.C, time is 150-480 min; the concentration of the nitriding agent in the nitriding furnace is 22-28%, and CO 3 2- The concentration is 15-21%; the resulting dense Fe 3 N、Fe 4 N and an intermediate nitrogen-containing austenite layer and a saturated or supersaturated nitrogen-containing solid solution therein;
putting the hydraulic cylinder matrix into an oxygen permeation furnace for oxygen permeation treatment; the oxygen permeation temperature is 350-550 ℃, and the time is 30-60 min; to obtain Fe of the surface 3 O 4 ；
Cleaning the inner surface of the base body of the hydraulic cylinder;
step six, polishing the inner surface of the base body of the hydraulic cylinder;
seventhly, putting the inner surface of the polished hydraulic cylinder substrate into an oxygen permeation furnace for oxygen permeation treatment; the oxygen permeation temperature is 400-550 ℃, and the time is 45-120 min; to obtain Fe 3 O 4 And (5) oxidizing the film.
The process has the advantages that:
the composite permeable layer with a three-layer structure can be formed by the process, and the wear resistance and the corrosion resistance of the composite permeable layer can be effectively improved.
Further, after the seventh step, placing the hydraulic cylinder base body into an aging furnace to perform aging treatment on the inner surface of the hydraulic cylinder base body; the aging temperature is 120-300 ℃, and the time is 60-300 min.
After aging treatment, the strength and hardness of the treated composite seeping layer are effectively improved.
Further, after the seventh step, the cylinder base body is placed in the seal groove to seal the inner surface of the cylinder base body.
By performing sealing treatment in the seal groove, corrosion resistance and wear resistance are improved.
Further, in the fifth step, the hydraulic cylinder base body is placed in a hot water cleaning tank, and hot water cleaning treatment is carried out on the inner surface of the hydraulic cylinder base body; the cleaning temperature is 20-80 ℃, and the cleaning time is 5-30 min.
The hot water cleaning is helpful for cleaning the hydraulic cylinder matrix quickly.
Further, in the sealing treatment step, a hot water sealing mode is adopted.
The hot water sealing mode is simple and quick, and the operation is convenient.
Further, the hydraulic cylinder base body is an outer cylinder, a middle cylinder, a plunger or a piston rod of the hydraulic support for the underground coal mine.
The process is suitable for the outer cylinder, the middle cylinder, the plunger or the piston rod of the hydraulic support of the underground coal mine hydraulic cylinder.
The second generation QPQ technology is a great technical breakthrough in the technical field of metal surface strengthening and corrosion prevention, can greatly improve the corrosion resistance and wear resistance of the treated piston rod and the hydraulic cylinder, and can replace the original chromium electroplating process of the piston rod, thereby greatly expanding the application range of the second generation QPQ technology in the field of hydraulic systems and generating remarkable social benefit and economic benefit. Meanwhile, the pollution of hexavalent chromium to the environment can be reduced and eliminated.
The second generation QPQ treatment technology is a pollution-free environment-friendly technology, and a large amount of application of the QPQ treatment technology can replace harmful processes such as hard chromium plating, salt bath cyaniding, salt bath soft nitriding and the like which seriously pollute the environment, and has great significance for improving the environment-friendly lagging state of metal surface strengthening in China.
Drawings
Fig. 1 is a schematic diagram of a first embodiment of the invention.
Detailed Description
The following is further detailed by way of specific embodiments:
reference numerals in the drawings of the specification include: compound layer 1, intermediate layer 2, diffusion layer 3, and base 4.
Example one
The embodiment is basically as shown in the attached figure 1: the composite permeable layer formed in the embodiment is suitable for products such as a cylinder, a plunger, a piston rod and the like in a hydraulic support for the underground coal mine.
In the composite seepage layer of the hydraulic cylinder in the embodiment, a compound layer 1 is formed on the inner surface of the hydraulic cylinder, and mainly comprises a surface Fe 3 O 4 Dense Fe 3 N、Fe 4 N, the thickness is 20-100 mu m, and the hardness reaches HV 0.1800-1100; the middle layer 2 is a nitrogen-containing austenite layer with the thickness of 10-80 mu m; the diffusion layer 3 is mainly composed of over-saturated or saturated nitrogen-containing solid solution, and has a thickness of 150-700 μm. Meanwhile, the corrosion resistance of the composite wear-resistant anticorrosive layer in a salt spray test reaches 500-1200 hours.
Can solve the pollution problem of hexavalent chromium in the hard chromium plating process, and can greatly improve the wear resistance and the corrosion resistance of the hydraulic cylinder.
The process can form a wear-resistant anticorrosive layer with the thickness of 20-100 mu m on the inner surface of the treated hydraulic cylinder, and the corrosion resistance of the salt spray test of the wear-resistant anticorrosive layer reaches 500-1200 hours.
In the QPQ treatment process of the composite permeable layer of the hydraulic cylinder in the embodiment, 27SiMn steel which is a special material for the hydraulic cylinder is adopted to carry out the second generation QPQ treatment process; the hydraulic support is suitable for products such as an outer cylinder, a middle cylinder, a plunger, a piston rod and the like of a hydraulic support for underground coal mines; the method comprises the following steps:
the inner surface of the hydraulic cylinder is subjected to ultrasonic cleaning and oil removal in a second generation QPQ special ultrasonic cleaning machine (with a heating function and a special cleaning agent);
preheating the inner surface of the hydraulic cylinder in a second generation QPQ special preheating furnace; preheating at 320-480 deg.c for 30-240 min;
nitriding the inner surface of the hydraulic cylinder in a second generation QPQ special nitriding furnace; nitriding temperature is 380-650 deg.C, time is 150-480 min. The concentration of the nitriding agent in the nitriding furnace is 22-28%, and the concentration of CO 32-is 15-21%. Obtaining compact Fe3N, fe4N, an intermediate nitrogen-containing austenite layer and a saturated or supersaturated nitrogen-containing solid solution in the austenite layer;
carrying out oxygen permeation treatment on the inner surface of the hydraulic cylinder in a second generation QPQ special oxygen permeation furnace; the oxygen permeation temperature is 350-550 ℃, and the time is 30-60 min.To obtain surface Fe 3 O 4 ；
The inner surface of the hydraulic cylinder is subjected to hot water cleaning treatment in a second generation QPQ special hot water cleaning tank; the cleaning temperature is 20-80 ℃, and the cleaning time is 5-30 min;
polishing the inner surface of the hydraulic cylinder in a second generation QPQ special polishing machine;
carrying out oxygen permeation treatment on the inner surface of the polished hydraulic cylinder in a second generation QPQ special oxygen permeation furnace; the oxygen permeation temperature is 400-550 ℃, and the time is 45-120 min. Obtaining Fe with black and bright surface 3 O 4 An oxide film;
carrying out aging treatment on the inner surface of the polished hydraulic cylinder in a second generation QPQ special aging furnace; the aging temperature is 120-300 ℃, and the time is 60-300 min;
and the inner surface of the hydraulic cylinder is subjected to sealing treatment in the second generation QPQ special sealing groove.
By adopting the process, the infiltration speed is fast, the infiltration is more stable, and the emission is less.
Compared with the first generation process, the treatment temperature range is wider, the treatment temperature of the first generation salt generally cannot be higher than 580 ℃, and the redness is aged when the treatment temperature of the first generation salt is higher than 580 ℃. The second generation process has simpler operation, less limitation on the treatment temperature range, wide use temperature range, stable salt and less discharge, can be used from 380 ℃ to 650 ℃, and can be used for QPQ treatment of deep and ultra-deep layers.
The process has strong practical value, solves the problems of poor corrosion resistance and wear resistance and the like when the hydraulic cylinder is actually used, improves the wear resistance of the hydraulic cylinder treated by the process by 20 times, and improves the corrosion resistance by 10 times.
Simple process and low cost. The second generation QPQ treatment process related to the process is simple to operate, and the treatment cost is greatly reduced compared with the traditional chromium plating process.
The scheme does not depend on special equipment, adopts general equipment, and can manufacture the composite permeable layer with the structure according to the process steps of the scheme.
Example two
Compared with the first embodiment, the hot water sealing mode is adopted in the first embodiment, and hot water with the temperature of 90-110 ℃ and the pH value of 6-7.5 is added into the sealing groove for 15-30 min. In this example, hot water at 105 ℃ and PH 7 was used for 25min for hot water sealing, and distilled or deionized water was used for sealing.
EXAMPLE III
Compared with the first embodiment, in the present embodiment, after the hydraulic cylinder substrate is placed in the nitriding furnace or the oxygen permeation furnace, the ionic permeation agent is added, the mixture is stirred for 9-14 min, then the vacuum pumping is performed, the pressure is maintained for 10-30 s, and then the nitriding or oxygen permeation operation in the first embodiment is started.
The composite seepage layer uniformly distributed on the surface of the hydraulic cylinder base body can be formed through the embodiment.
The foregoing is merely an example of the present invention, and common general knowledge in the field of known specific structures and characteristics is not described herein in any greater extent than that known in the art at the filing date or prior to the priority date of the application, so that those skilled in the art can now appreciate that all of the above-described techniques in this field and have the ability to apply routine experimentation before this date can be combined with one or more of the present teachings to complete and implement the present invention, and that certain typical known structures or known methods do not pose any impediments to the implementation of the present invention by those skilled in the art. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be defined by the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.
Claims (6)
1. A QPQ treatment process of a composite infiltrated layer is characterized by comprising the following steps: the composite seepage layer is positioned on the inner surface of the hydraulic cylinder and comprises a compound layer, an intermediate layer and a diffusion layer which are sequentially stacked from inside to outside; the compound layer is composed of surface Fe 3 O 4 Dense Fe 3 N、Fe 4 N is formed; the compound layer has a thickness of 100 μm and a hardness of HV 0.1 800 to 1100; the middle layer is a nitrogen-containing austenite layer, and the thickness of the middle layer is 80 mu m; the thickness of the diffusion layer is 700 μm; the compound layer is a composite wear-resistant anticorrosive layer;
the QPQ treatment process comprises the following steps:
cleaning a liquid pressure cylinder substrate;
secondly, the hydraulic cylinder is basically placed in a preheating furnace for preheating treatment, the preheating temperature is 320-480 ℃, and the time is 30-240 min;
thirdly, putting the preheated hydraulic cylinder matrix into a nitriding furnace for nitriding treatment; nitriding temperature is 380-650 ℃, and nitriding time is 150-480 min; the concentration of nitriding agent in the nitriding furnace is 22-28%, and CO is 3 2- The concentration is 15-21%; the resulting dense Fe 3 N、Fe 4 N and an intermediate nitrogen-containing austenite layer and a saturated or supersaturated nitrogen-containing solid solution therein;
putting the hydraulic cylinder matrix into an oxygen permeation furnace for oxygen permeation treatment; the oxygen permeation temperature is 350-550 ℃, and the time is 30-60 min; to obtain Fe of the surface 3 O 4 ；
Cleaning the inner surface of the base body of the hydraulic cylinder;
step six, polishing the inner surface of the base body of the hydraulic cylinder;
seventhly, putting the inner surface of the polished hydraulic cylinder substrate into an oxygen permeation furnace for oxygen permeation treatment; the oxygen permeation temperature is 400-550 ℃, and the time is 45-120 min; to obtain Fe 3 O 4 And (5) oxidizing the film.
2. The QPQ treatment process for composite infiltrated layers according to claim 1, characterized in that: after the seventh step, the hydraulic cylinder base body is placed into an aging furnace to perform aging treatment on the inner surface of the hydraulic cylinder base body; the aging temperature is 120-300 ℃, and the time is 60-300 min.
3. The QPQ treatment process for a composite carburized layer according to claim 2, characterized in that: and after the seventh step, putting the hydraulic cylinder base body into the sealing groove to seal the inner surface of the hydraulic cylinder base body.
4. The QPQ treatment process for a composite carburized layer according to claim 1, characterized in that: putting the hydraulic cylinder substrate into a hot water cleaning tank, and performing hot water cleaning treatment on the inner surface of the hydraulic cylinder substrate; the cleaning temperature is 20-80 ℃, and the cleaning time is 5-30 min.
5. The QPQ treatment process for the composite infiltrated layer according to claim 3, wherein: in the sealing treatment step, a hot oil sealing mode is adopted.
6. A composite permeable layer, comprising: the QPQ treatment process according to claim 1 is employed.
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| CN202545796U (en) * | 2011-11-29 | 2012-11-21 | 青岛张氏机械有限公司 | Deep surface treatment piston rod |
| CN109778110A (en) * | 2018-12-27 | 2019-05-21 | 陕西铁马铸锻有限公司 | A kind of anticorrosion antiwear slider bed platform slide plate and treatment process |
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| CN105441865A (en) * | 2015-12-02 | 2016-03-30 | 成都锦汇科技有限公司 | QPQ treatment process suitable for cylinder sleeve |
| CN105441869A (en) * | 2015-12-23 | 2016-03-30 | 四川全丰新材料科技有限公司 | QPQ (Quench-Polish-Quench) nitriding co-permeation treatment process |
| CN107177817A (en) * | 2017-03-31 | 2017-09-19 | 江苏科技大学 | It is a kind of while improving the handling process of carbon steel corrosion stability and wearability |
| CN111575710A (en) * | 2020-05-14 | 2020-08-25 | 成都工具研究所有限公司 | Treatment process for improving wear resistance and corrosion resistance of 40CrNiMoA structural steel and 40CrNiMoA structural steel part |
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